茶树β-淀粉酶基因CsBAM3的克隆及其响应低温的表达模式

发布时间：2018-03-30 13:09

  本文选题：β淀粉酶　切入点：茶树　出处：《作物学报》2017年10期

【摘要】：β-淀粉酶(BAM)是植物中参与淀粉水解的关键酶类,在应对非生物胁迫中发挥重要作用。从前期茶树冷驯化转录组分析中分离到1个参与淀粉代谢的差异表达基因,cDNA全长克隆及序列分析鉴定该基因为拟南芥BAM3同源基因,命名为CsBAM3。该基因编码548个氨基酸残基,与拟南芥的BAM1和BAM3一起归为第Ⅱ亚家族,推测为叶绿体定位、具有淀粉水解活性的β-淀粉酶编码基因。启动子克隆及序列分析显示该基因可能受生理节律、光、低温及多种激素等信号共同调控。CsBAM3在叶片中表达量最高,茎和花中表达量较低,根中基本不表达。CsBAM3在冷驯化初期被显著上调且一直保持相对较高的水平。成熟叶片及嫩芽(一芽二叶)中的CsBAM3均可以被4℃及0℃低温显著上调,且嫩芽中基因的表达量上调幅度明显高于成熟叶。模拟倒春寒低温条件下,检测不同萌发阶段新梢中CsBAM3的表达情况表明,CsBAM3在鲜叶初展的嫩芽中即可快速受低温诱导。以上结果表明,CsBAM3是茶树中调控淀粉水解的一个重要β淀粉酶编码基因,在茶树成熟叶和嫩芽受到不同低温胁迫时其表达可被快速诱导。
[Abstract]:尾 -amylase (尾 -amylase) is the key enzyme involved in starch hydrolysis in plants. A differentially expressed gene involved in starch metabolism was cloned and sequenced to identify the homologous gene of Arabidopsis thaliana BAM3 in Arabidopsis thaliana. CsBAM3.The gene encodes 548 amino acid residues and belongs to the second subfamily along with BAM1 and BAM3 of Arabidopsis thaliana. 尾 -amylase encoding gene with starch hydrolysis activity. Cloning and sequence analysis of promoter showed that the gene may be regulated by physiological rhythm, light, hypothermia and multiple hormones. CsBAM3 is the most expressed gene in leaves. The expression of CsBAM3 in stem and flower was low, the expression of .CsBAM3 in root was significantly up-regulated at the beginning of cold acclimation and maintained a relatively high level. The CsBAM3 in mature leaves and tender buds (one bud and two leaves) could be upregulated at 4 鈩，

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